3,5-Dimethoxybenzaldehyde → 1-(3,5-Dimethoxyphenyl)-8-bromo-1-octen-3-one

Beteiligte Stoffe

Reaktionsschritte

1.13 parts of [(2-oxepanylidene)methyl] triphenylphosphonium bromide having the formula ##STR11## was suspended and 0.83 part of 3,5-dimethoxybenzaldehyde was dissolved in 45 parts of xylene as the aprotic medium. This mixture was maintained under a nitrogen atmosphere and was refluxed for 24 hours and was then cooled to room temperature. Xylene was removed from the resulting clear solution at a temperature of about 60° C. and under reduced pressure. The remaining traces of xylene were removed in a drying oven at a temperature of about 50° C. and under a reduced pressure of about 0.5 millimeter of mercury. The resulting product mixture was separated chromatographically in a silica gel column using a benzene elution solvent, to isolate 1-(3,5-dimethoxyphenyl)-8-bromo-1-octen-3-one which, after recrystallization from benzene, melted at about 73°-76° C.

Herkunft & Nachweise